Antiparasitics Flashcards
Drug treatment used for each cestode?
Taenia saginata :
Taenia solium:
Cysticercosis:
Diphyllobothrium tatum:
Echinococus glanulosus:
E. multilocularis:
Taenia saginata Praziquantel, mebendazole, niclosamide
Taenia solium Praziquantel, niclosamide
Cysticercosis Praziquantel, niclosamide
Diphyllobothrium tatum Praziquantel
Echinococus glanulosus Albendazole
E. multilocularis Albendazole
Drug treatment for each trematode?
S. mansoni, S. japonicum:
Schistocoma hematobium:
Clonorchis sinensis:
S. mansoni, S. japonicum Praziquantel
Schistocoma hematobium Praziquantel
Clonorchis sinensis Praziquantel,
albendazole
Treatment option for listed nematode
Ascaris lumbricoides:
Trichinella spiralis
Enterobius vermicularis:
Necator americanes;
Ancylostoma duodenale
(Hookworms)
Ascaris lumbricoides
Mebendazole, albendazole,
pyrantel pamoate
Trichinella spiralis
Mebendazole or albendazole;
add corticosteroids for severe infection
Enterobius vermicularis
Pyrantal pamoate or mebendazole
Necator americanes;
Ancylostoma duodenale
(Hookworms)
Pyrantel pamoate or mebendazole or albendazole
Treatment option for listed nematode:
Trichuriasis Trichuris trichiura (whipworm):
Onchocerciasis (River Blindness) Onchocerca volvulus:
Visceral larva migrans (Toxocariasis) Toxocara canis, Toxocara cati
Lymphatic filariasis Wuchereria bancrofti,
Brugia malayi:
Loiasis Loa loa (African eye worm):
Strongyloidiasis Strongyloides stercoralis
(threadworm):
Trichuriasis Trichuris trichiura
(whipworm)
Mebendazole or albendazole
Onchocerciasis (River Blindness) Onchocerca volvulus
Ivermectin
Visceral larva migrans (Toxocariasis)
Toxocara canis, Toxocara cati
Albendazole
Lymphatic filariasis Wuchereria bancrofti,
Brugia malayi
Diethylcarbamazine
Loiasis
Loa loa (African eye worm)
Diethylcarbamazine
Strongyloidiasis Strongyloides stercoralis
(threadworm)
Ivermectin
Niclosamide clinical uses, moa, and AE?
• second-line treatment of beef, pork, and fish tapeworms and an alternative drug for small
and large intestinal flukes.
• act by uncoupling oxidative phosphorylation within parasites.
• Adverse effects are usually mild, although, as with other anthelminthics, allergic
reactions from dying parasites can occur
Praziquantal uses, activity, moa, and AE?
• First-line medication for fluke infections.
• increases membrane permeability to calcium, leading to muscle contractions followed by paralysis and parasite death.
• Praziquantel is highly active against most trematodes.
• Treatment of choice for schistosomiasis, intestinal flukes, and beef, pork, and fish tapeworms.
• Generally well tolerated.
• Neurologic adverse effects can be seen in the treatment of neurocysticercosis, with
corticosteroids often used as pretreatment.
Pyrantel pamoate moa, activity, doc indications?
• activates nicotinic acetylcholine receptors within parasites, causing persistent muscle
contraction followed by depolarized paralysis.
• highly active against adult nematode worms, but not their eggs.
• Drug of choice for hookworm and roundworm infections but is inactive against tapeworms and flukes.
• poorly absorbed and is generally well tolerated but can cause gastrointestinal side effects.
Diethylcarbamazine moa, clinical indication, and ae?
• Diethylcarbamazine, which paralyzes microfilariae by an unknown mechanism
• It is the drug of choice for filarial infections caused by Brugia malayi, Wuchereria
bancrofti, and Loa loa (eye worm disease).
• Common adverse effects include headache, weakness, and malaise. Reactions to dying
parasites can trigger allergic reactions.
Ivermectin clinical use, moa,, pk, and AE?
• first-line therapy for nematode infections, including onchocerciasis, cutaneous larva
migrans, and strongyloidosis.
• enhances GABA neurotransmission in nematodes, causing their paralysis.
• does not cross the blood-brain barrier, CNS side effects are not seen.
• Adverse effects are often related to reactions to dying worms, including rashes, pruritus,
fever, hypotension, and joint pain. These symptoms often can be minimized by pretherapy with NSAIDs and antihistamines.
• Not be used in pregnant women due to teratogenic potential.
Thiabendazole activity, AE, and contraindications?
- closely related to mebendazole and albendazole.
- It is active against strongyloidosis and trichinosis but is not a first-line drug because of its adverse effects- which include hematuria, allergic reactions (including Stevens-Johnson syndrome), and liver failure
- Thiabendazole should not be used to treat pregnant women and patients with liver or kidney problems
AE of mebendazole?
• Similar to albendazole
• The main adverse effect is gastrointestinal irritation but agranulocytopenia and
alopecia at high dosages
Albendazole moa, activity, and ae?
• blocks glucose uptake and microtubule assembly within parasites.
• wide spectrum of activity and is the primary drug for ascariasis, hookworm,
pinworm, and whipworm infections.
• Albendazole is also active against the pork tapeworm in the larval stage
(cysticercosis).
• Adverse effects can include alopecia and elevated levels of liver enzyme, but the
drug is generally well tolerated .
Treatment for Trypanosoma
brucei?
Suramin: East African
Pentamidine: West African
Melarsoprol: severe
Treatment for T. cruzi?
Nifurtimox or benznidazole
treatment for Leishmania
donovani?
Stibogluconate or amphotericin, pentamidine
Treatment of Plasmodium
falciparum?
Quinine derivatives or
artesuate Atovaquone/
proguanil
Treatment of Toxoplasma
gondii
Pyrimethamine plus
sulfa or clindamycin
Treatment of Giardia lamblia & Trichomonas
vaginalis
Metronidazole
Treatment of Pneumocystic jiroveci infections
Trimethoprim-sulfamethoxazole
cotrimoxazole
Leishmaniasis therapy, moa, activity, pk, ae, and alternatives?
Stibogluconate is the main drug used for treating leishmaniasis.
• It is an unusual compound that contains the element antimony; hence the Stibo.
• The pentavalent antimony inhibits glycolysis in the parasite.
• Stibogluconate is active in all forms of leishmaniasis, including cutaneous,
mucocutaneous, and visceral effects.
• This antiparasitic agent must be administered intravenously and can produce toxic cardiac effects, including prolongation of the QT interval
• Alternative agents include pentamidine for visceral leishmaniasis and fluconazole or metronidazole for cutaneous lesions.
Chagas disease therapy
• Nifurtimox, the traditional treatment, is no longer available in the United States.
• Melarsoprol is the most effective option but carries risk of severe toxicity (even death) as
described above.
• Benznidazole is a newer antibiotic that has an unclear mechanism of action.
Therapy approach for African sleeping sickness?
- drug protocol of choice for early stage is suramin combined with pentamidine.
- Suramin has an unclear mechanism of action but is associated with several CNS and bone marrow toxicities.
- Late stage of African sleeping sickness is very difficult to treat.
- Melarsoprol is an arsenic-containing drug that can cause death due to toxicity.
- Melarsoprol should be reserved for severe cases.
Pyrimethamine and clindamycin or sulfdiazine?
• Pyrimethamine-clindamycin or pyrimethamine sulfadiazine are the primary treatments and prophylaxis for Toxoplasma gondii.
• Adverse effects of pyrimethamine can include folic acid depletion. Hypersensitivity
reactions can also occur.
Metronidazole and tinidazole compare and contrast?
• Used for: Parasitic infections and Anaerobic bacterial infections.
• Tinidazole has similar efficacy but is more expensive than metronidazole.
• taken up by protozoa or anaerobic bacteria and converted to a toxic metabolite by ferroreduction
• orally or intravenously administered
• Resistance to these drugs is rare.
• Effective treatment for: • Amebiasis (Entamoeba histolytica)
• Giardiasis (Giardia Lambiia)
• Trichomoniasis (Trichomonas)
• Metronidazole has an unpleasant taste and can also cause a disulfiram-like reaction with
ethanol due to inhibition of aldehyde dehydrogenase
List 3 intestinal antiparasitics?
- Diloxanide furoate
- Iodoquinol
- Paromomycin
Iodoquinol moa, pk, activity, and ae?
• Unclear mechanism
• low absorption through the gastrointestinal tract and is thus used to eradicate parasites
within the intestines
• Some Entamoeba histolytica have resistance to iodoquinol due to overexpression of the
P-glycoprotein pump
• Predominantly used for amebic dysentery.
• Adverse Effects Iodoquinol contains iodine and can cause allergic reactions.
Neurotoxicity is a rare side effect.
List 3 systemic anti parasites?
- Chloroquine
- Emetine
- Dehydroemetine
- Useful for treating liver abscesses or intestinal wall infections
Drug of choice and alternative for asymptomatic, intestinal infection?
DOC: Diloxanide furoate
Alternative: Iodoquinol, paromomycin
Drug of choice and alternative for mild to moderate intestinal infection:
DOC: Metronidazole + diloxanide furoate
Alternative: Tinidazole, or tetracycline, or erythromycin + diloxanide furoate
Drug of choice and alternative for severe intestinal infection:
DOC: Metronidazole or tinidazole + diloxanide furoate
Alternative:Tetracycline or emetine or dihydroemetine + diloxanide furoate
Drug of choice and alternative for Hepatic abcess and other extraintestinal disease
DOC: Metronidazole or tinidazole + diloxanide furoate
Alternative: Emetine or dihydroemetine +
chloroquine + diloxanide
furoate
